One question per week: What are the impacts of global climate anomalies and environmental degradation?

This post was last edited by ray1513 on 2011-6-13 09:49. Global climate anomalies, the causes of climate warming, background knowledge on the factors leading to climate anomalies, theoretical explanations, and ways to address global climate anomalies include afforestation to protect the ecological environment, developing new energy sources, and promoting clean energy technologies. Causes of climate warming, factors causing climate anomalies, background knowledge, theoretical explanations, and solutions to global climate anomalies: afforestation to protect the ecosystem, development of new energy sources, and promotion of clean energy technologies. Expand: Causes of climate warming. Global climate anomalies refer to a range of abnormal weather phenomena worldwide, such as global warming and an increasing frequency of extreme weather events. Causes of climate anomalies 　If the Earth is viewed as a system, over time it develops a stable energy exchange mechanism with its surroundings, becoming an equilibrium system. When one or more components within the energy exchange system experience abnormalities or disruptions, it leads to abnormalities in the entire system as well; moreover, such abnormalities are chaotic, making it difficult to establish a new equilibrium. Problems have arisen, and the balance has been disrupted; however, no new balance has been established, and the system remains in a state of disorder. The series of phenomena that result from this include: 1. Abnormalities in the global climate, 2. Abnormalities in plate movements, 3. Abnormalities in ocean currents… and a whole range of other abnormalities. All of these abnormalities, ultimately, follow the most fundamental laws of physics. Mathematical models can be developed using these laws to predict such phenomena, and this is precisely what makes geophysics so fascinating. 　Recent research by Chinese scientists shows that there is an inevitable intrinsic connection between the ongoing reduction in vegetation coverage on the Earth’s surface and global climate anomalies; first, a brief introduction to this mathematical model will be provided. Background Knowledge First, it is necessary to introduce some basic physical principles: First, mechanics ； 　　Second, Joule’s Law. The British physicist Joule conducted numerous experiments, and in 1840 he determined with precision that the heat generated when an electric current flows through a conductor is proportional to the square of the current, to the resistance of the conductor, and to the time during which electricity flows through it. This law is known as Joule’s Law. Joule’s Law can be expressed using the formula Q=I2Rt. Third, the photoelectric effect ； 　　When light shines on certain substances, it causes changes in their electrical properties; in other words, light energy is converted into electrical energy. This type of photoelectric phenomenon is collectively referred to as the Photoelectric effect. 　　The photoelectric effect is divided into photoelectron emission, photoconductive effect, and photovoltaic effect. The former phenomenon occurs on the surface of an object; it is also known as the external photoelectric effect. The latter two phenomena occur within the object and are known as the internal photoelectric effect. 　　Hertz discovered the photoelectric effect in 1887, and Einstein was the first to successfully explain it. 　　Fourth, the tip discharge effect ； 　　Fifth, the law of electromagnetic induction ； 　　Sixth, the concept of field distribution... In short, it involves the four fundamental forces of mechanics—force, heat, light, and electricity—as well as theories from modern physics; knowledge of advanced mathematics and aspects such as tectonic plate movements is also necessary. Theoretical derivation: With this knowledge, it is possible to understand the following statements. (1) Major premise: The Earth rotates on its axis while orbiting the Sun; the angle between the ecliptic and the equator is 23 degrees 26 minutes. Under the influence of solar radiation, the electrons in surface objects are continuously ionized due to the photoelectric effect. The resulting negative ions rise along with the hot air, causing the Earth’s surface to acquire a positive charge. The magnitude of this charge is directly proportional to the intensity of solar radiation and the duration of exposure. In other words, the Sun continuously charges the Earth’s surface positively, while the negative ions rise to higher altitudes. Thus, the entire Earth’s surface together with the atmosphere forms a gigantic capacitor. 　　(2) How will the charge be distributed on the Earth’s surface? 　　Since seawater is a good conductor, whereas continental plates are poor conductors, electricity can flow rapidly at sea level, but more slowly on the continents. Due to the tip effect, charge accumulates in areas at higher elevations on the Earth’s surface; as a result, the overall current effect at sea level is zero, and the current effects are primarily observed in the continental plates. In this way, an electrical current and charge model of the Earth can be established based on basic parameters such as the distribution of tectonic plates, the detailed topographical features of the Earth’s surface, the Earth’s rotation, and the angle of solar radiation. The distribution patterns can be calculated, and in theory, results that are very accurate compared to the actual conditions can be obtained, depending on the precision of the parameter selection and the computer’s data processing capabilities. 　　(3) The resulting current field distribution and the mechanism behind the generation of the geomagnetic field. When one side of the Earth faces the Sun, according to this theoretical model, if all external solar radiation is blocked, the charge movements on the Earth’s surface tend to move toward the pointed areas, thereby creating a current field 1, which is referred to as magnetic field 1. This current field is related to the distribution of continents on the Earth’s surface as well as their elevations; since the currents are isotropic, their overall effect is zero, but they can still influence the distribution of the geomagnetic field in local areas ； At the same time, the Earth’s surface is constantly discharging electricity. Therefore, in the presence of solar radiation, the charge distribution on the side of the Earth facing the Sun (which is mainly found on the continents) is such that there is the most charge on the eastern side and the least on the western side (due to the Earth’s rotation from west to east). As a result, an electric current flows from east to west on the side facing the Sun; this is referred to as Current Distribution 2. This current generates a magnetic field, known as Magnetic Field 2. It can be seen that the magnetic field is stronger on the side facing the Sun, while it weakens on the side facing away from the Sun ； Furthermore, the magnitude of the magnetic field generated by the Earth’s rotation due to the positive charge accumulated in the surface tip region can be referred to as magnetic field 3 ； The negative charges above the Earth’s surface also generate an electric current field 4 as the Earth rotates; this corresponds to a magnetic field, which can be termed Magnetic Field 4. Since the total amounts of positive and negative charges are equal, the overall effect of Magnetic Field 3 and Magnetic Field 4 is zero. In summary, magnetic field 2 is the main source of the Earth’s magnetic field; specific values require model calculations based on detailed data such as solar radiation levels and the distribution of continental plates. 　　(4) How does the Earth achieve charge balance? The Earth can be regarded as a supercapacitor; while the Sun charges this supercapacitor at a rate of 1600 A, it also discharges electricity at the same rate of 1600 A (as indicated in Feynman’s Lectures on Physics, where the average current of lightning is 1600 A, which implies that the charging current is also 1600 A). This discharge is what constitutes lightning. Therefore, the average current of lightning on Earth is 1600 A, and the current from lightning flows from the Earth’s surface upward into the sky. Lightning requires breaking through the air, so it occurs more frequently in areas with high air humidity, such as during rainy and windy weather, as well as in volcanic crater regions at higher altitudes. The surface electric field strength on Earth exceeds 100 V/m from the ground up (see Feynman’s Lectures on Physics); the electric field distribution extends from the surface all the way to the ionosphere. Therefore, it can be inferred that this Earth-based supercapacitor holds a great deal of energy. Since the amount of electric charge is so large, why don’t we feel anything? Because we are at the same potential, and dry air is an excellent insulator, we don’t feel anything. 　　(5) What problems will arise if surface vegetation decreases? 　　From the above points, it can be seen that the Earth’s large capacitance is a balanced system. For a long time, the ecological environment and vegetation cover on Earth have remained relatively stable. Consequently, the water content on the surface has also been relatively stable, and thus the surface conductivity has remained relatively constant. According to this theory, when surface vegetation decreases, the electrical conductivity of the surface drops, which means an increase in resistance. In other words, the internal resistance of the Earth’s capacitor increases, while the charging power, namely solar radiation, remains relatively stable. According to Joule’s law, this leads to an increase in heat generation at the surface, thereby contributing to global warming to a certain extent. 　　(6) What will happen if a large amount of surface vegetation disappears or if there is widespread drought? 　　If vegetation disappears on a scale of thousands of kilometers or if drought occurs, large areas of the surface become insulators, preventing electricity from flowing as it normally would; as a result, a large amount of charge accumulates on the surface. Due to the Coulomb force between charges, this manifests intuitively as cracks forming on the land surface; macroscopically, it appears as tensile stress on the respective continental plates. The form of energy involved is elastic potential energy. The longer the drought lasts, the greater the amount of energy accumulated. When moist air moves into this area, the ground once again becomes a better conductor due to the moisture from the rain; the large amount of charge accumulated on the surface moves rapidly toward the sharp points, resulting in heavy rainfall accompanied by numerous lightning strikes. This rapid release of energy causes abnormal movements in the continental plates. This release of energy is negligible for the Earth, but extremely destructive for humans. 　　It can be seen from this model that the continuous decline in surface vegetation is one of the main driving forces behind global climate anomalies. As surface temperatures rise slowly, various abnormal weather phenomena occur more frequently, with complex interactions at play; more detailed data from various fields such as the atmosphere, ocean currents, and geology are needed. This model can serve as a fundamental model in geophysics. Analyze specific problems on a case-by-case basis; this approach can also be applied to other celestial bodies and galaxies. 　　Unrestrained human activities are the two main causes: on one hand, they lead to the emission of greenhouse gases that trigger the greenhouse effect, and on the other hand, excessive acid rain results in a reduction of vegetation. These two factors together exacerbate climate anomalies.

The global climate system is extremely complex, with numerous factors influencing climate change, including solar radiation, the composition of the atmosphere, oceans, land areas, and human activities. There is still uncertainty in scientific understanding regarding climate change trends; in particular, it is not possible to make accurate assessments of the climate change trends in different regions, as well as their specific impacts and consequences. However, from the perspective of risk assessment, most scientists assert that climate change represents a major environmental risk facing humanity. 1. Impacts of sea-level rise: Over the past century, sea levels have risen by 14.4 cm, with an increase of 11.5 cm in our country. The main cause of rising sea levels is the thermal expansion of seawater; as the oceans warm up, sea levels rise. Global warming causes icebergs at both the North and South Poles to melt; this is one of the main reasons for the rise in sea levels. The direct effects of sea-level rise include the following: (1) Flooding of low-lying areas: The UK is raising its levees in response to climate change. Global warming causes sea levels to rise and increases the frequency of storms; as a result, the British must raise their flood control barriers. According to statistics released by British authorities recently, over the past 20 years, as the water level of the Thames has risen due to global warming, local **authorities have had to raise flood defenses 88 times in order to protect the lives and property of Londoners. It is reported that people now raise their dams 4 times a year on average. It is estimated that by 2030, the frequency of raising its levees will reach 30 times per year. (2) Coastline erosion (3) Increased salinity in surface and groundwater, affecting urban water supply. (4) Rise in groundwater level. (5) The tourism industry is harmed (with a sea level rise of 50 meters, the coastal tourism areas in Dalian, Qinhuangdao, Qingdao, Beihai, and Sanya will retreat by 31–366 meters; 24% of the beaches will be lost, while 60% of the beaches in Beidaihe will be lost). According to the 2002 China National Land and Resources Bulletin, coastal tourism had become the largest industry, with an output value of 250.3 billion yuan, accounting for 34.6% of the total output value of the marine industry. (6) It affects the lives of residents in coastal and island countries (who account for one-third of the world’s population), putting them at risk. If the polar ice caps melt, economically developed and densely populated coastal areas will be submerged by seawater. Low-lying island nations such as the Maldives and Seychelles will disappear from the map, and major coastal cities like Shanghai, **, **, Rio de Janeiro, Tokyo, Bangkok, and New York, as well as countries such as Bangladesh, the Netherlands, and Egypt, will also not be spared this fate. 2. Effects on animals and plants: Climate is the main factor determining the distribution of biological communities. Climate change can alter the adaptability of different species in a region, as well as the competitiveness among various populations within an ecosystem. Animals and plants in nature, especially plant communities, may suffer tragic fates as they are unable to adapt to the pace of global warming and migrate in response. Past climate changes (such as ice ages) have caused many species to go extinct; future climates will cause certain species in some regions to disappear, while other species will benefit from warming climates – their habitats may expand, and their competitors and predators may decrease. Take oranges, for example. In the 1970s, their northernmost limit was along the Huangshan area; Xuanzhou City also tried to grow them there, but a heavy snowfall in winter caused the trees to die from the cold. But now, the orange trees on our campus are all growing well. For example, the Chinese alligator lives only in limited areas such as Xuancheng, Jingxian, and Nanling; if its northern boundary moves further north, it could go extinct naturally. This is in terms of specific areas within our province. Nationwide, China uses the 0-degree isotherm in January as the northern boundary of the subtropics; currently, this boundary lies in the Qinling-Huaihe region of China. Research shows that rising temperatures will cause this boundary to shift northward, beyond the Yellow River. In winter, temperatures in areas such as Xuzhou and Zhengzhou will be similar to those currently experienced in Hangzhou and Wuhan. 3. Impact on agriculture: The distribution of temperature and precipitation throughout the year are the main factors determining which crops can be grown. Temperature and the changes in precipitation caused by it affect the yield of food crops as well as the types of crops that can be cultivated. Climate changes have previously led to significant changes in the spatial (latitudinal) distribution of biotic zones and communities. If the average temperature in the North Atlantic region was 1°C higher between the years 800 and 1200, it would have made it possible to grow corn in Norway. However, during the period from 1500 to 1800, a mini ice age occurred in Western Europe, with average temperatures being only 1–2°C lower than they are today; as a result, half of the farms in Norway were abandoned, and almost all agricultural activities in Iceland came to a halt. In addition, global warming will also exacerbate natural disasters such as high temperatures, heatwaves, tropical storms, and tornadoes. Therefore, with rising global temperatures, there will be significant changes in the stability and distribution of world food production. 4. Impact on human health: Human health depends on a healthy ecological environment, and global warming will become a major factor affecting human health in the next century. Extreme heat will make health problems for humans more frequent and widespread in the next century. This is mainly reflected in an increase in morbidity and mortality rates. In particular, infectious diseases such as malaria, lymphatic filariasis, schistosomiasis, hookworm disease, cholera, meningitis, kala-azar, and dengue fever will pose a threat to tropical regions. Some diseases that currently occur primarily in tropical areas may spread to mid-latitude regions as the climate warms. If the population “explosion” is the first challenge facing humanity, then the worsening environmental pollution is the second challenge. ? Over the past century, the use of fossil fuels has increased by almost 30 times. Currently, about 21 billion tons of CO2 are emitted into the atmosphere worldwide each year, raising the concentration of CO2 in the atmosphere from 270×10‑6 in the first half of the 19th century to 344×10‑6 by 1980. It is expected that by 2030, the concentration of CO2 in the atmosphere will double to reach 680×10‑6. ? The “greenhouse effect” caused by CO2, etc., has led to a significant warming of the global climate. Scientists predict that by the middle of the next century, the average temperature at the Earth’s surface will rise by 1.5 to 4.5°C, resulting in partial melting of ice and snow at the North and South Poles. Together with the thermal expansion of seawater, this will cause the world’s sea levels to rise by 25 to 100 centimeters, and some low-lying coastal cities will be submerged under the sea. Many flat areas on Earth, such as cities like Beijing, Shanghai, London, and New York, were all flooded. Hundreds of millions of coastal residents will be forced to relocate. At the same time, global warming will lead to drought and little rainfall in many ** and regions, an increase in pests, and reduced agricultural yields. ? In addition, the amount of harmful gases such as SO?2 and nitrogen oxides emitted into the atmosphere worldwide each year is also increasing rapidly. When SO2 and nitrogen oxides in the atmosphere come into contact with water droplets or humid air, they are converted into sulfuric acid and nitric acid, which dissolve in rainwater, lowering its pH to below 5.6 (the normal value being 5.6); such rain is known as acid rain. When the concentrations of SO₂ and nitrogen oxides in the atmosphere are high, they can lower the pH of rainfall to around 3. A 1987 study by the U.S. Air Resources Research Laboratory showed that over 30 million people in the United States are currently affected directly by acid rain. As a result, the United States incurs direct losses of up to $15 billion per year. In Europe, **more than 50% of forests have been damaged by acid rain.** Due to forest destruction, by the year 2000 the number of species remaining in the world will drop to 1/5 to 1/4 of the current total, representing an irreversible ecological extinction. ? Since the beginning of this century, acid rain pollution has been spreading across the world, with its acidity continuing to increase. In both developed and developing countries, including my own country, acid rain is becoming an increasingly serious problem. ? In our country, SO?2 and other pollutants mainly come from the combustion of coal. According to measurements taken in 23 provinces and cities, acid rain was detected in 21 of them, accounting for over 90%. In China, the acidity of rainfall shows a gradual increasing trend from north to south. South of the Yangtze River, acid rain has become a fairly common problem; it is most severe in the Southwest and South China. In China’s North China, Northeast China, and Northwest China, acid rain used to be rare, but now it is also plaguing certain areas. Acid rain acidifies the quality of soil, lakes, and river water, deteriorates aquatic ecosystems, and harms the growth of crops and other plants. According to statistics, nearly 2.6 million hectares of farmland in our country are affected by acid rain each year, resulting in a reduction in crop yields of around 10%. In the four provinces and regions of Guangdong, Guangxi, Sichuan, and Guizhou alone, acid rain causes direct economic losses of 2.45 billion yuan per year, with even greater losses in terms of indirect ecological benefits. ? At the same time, acid rain also corrodes building materials, causing severe damage to monuments, historical buildings, sculptures, decorations, and other important cultural facilities; the losses resulting from this are difficult to estimate. ? It is reported that currently, around 420 billion cubic meters of wastewater are discharged into rivers, lakes, and seas worldwide each year, contaminating 5.5 trillion cubic meters of freshwater – which accounts for over 14% of the world’s total runoff. Experts predict that by the year 2000, the amount of wastewater discharged worldwide through sewers and industrial pipelines will reach 1.6 trillion to 2.1 trillion cubic meters. Rising incidence rates and deaths of aquatic organisms occur due to water pollution. The water supply crisis caused by water pollution is* spreading across the globe. The World Health Organization estimates that in 1980, about 3/5 of the people in developing countries had difficulty accessing safe drinking water, and around 1.8 billion people were at risk of illness due to consumption of polluted water. Approximately 25,000 people die each day as a result of drinking contaminated water, and in developing countries, 4/5 of child deaths are attributed to water-related diseases. According to experts, water pollution in our country alone results in economic losses of 15 billion yuan per year. If no effective measures are taken, the economic losses caused by water pollution during the 15-year period from 1985 to 2000 will reach 273.5 billion yuan. According to statistics from 1991, China’s annual emissions of waste gases amounted to 1.13 billion standard cubic meters; among these, the emission of dust was 16.15 million tons, SO2 emissions were 18.44 million tons, and there were around 1 million tons of other harmful gases. Many cities exceed the standard by several times. In the monitoring of total suspended particulate matter concentrations conducted in 41 cities around the world, China’s five major cities—Beijing, Shanghai, Shenyang, Guangzhou, and Xi’an—all made it into the top 10. Due to pollution, the air over cities is filled with smog, visibility decreases, sunny days become fewer, and smoggy days increase. Benxi City, which is severely polluted, has been listed as a “city invisible from space.” Severe air pollution directly endangers people’s health. In 1991, China’s overall mortality rate was 670 per 100,000, an increase of 0.5% compared to the previous year. Studies at home and abroad have shown that cancer is related to environmental factors, with lung cancer and air pollution being the most evident examples. Currently, cancer has become the leading cause of death among urban residents in our country, with a cancer mortality rate of 129.9 per 100,000 in large cities and 104 per 100,000 in smaller cities. Among cancers, lung cancer has the highest mortality rate. Lung cancer hotspots are mostly found in areas with early industrial development, high economic density, and severe air pollution. Among them, the rate in large cities is 35.2 per 100,000, while that in small and medium-sized cities is 23.7 per 100,000; these figures account for 27.1% and 22.1% of cancer deaths respectively, and there has been a clear upward trend in recent years. In rural areas, the proportion of cancer deaths in the total death rate is also increasing year by year. Respiratory diseases are the leading cause of death among residents in rural areas, and air pollution is one of the main factors contributing to respiratory diseases, particularly chronic bronchitis. Every year, more than 3 million people worldwide die from cancers caused primarily by environmental pollution. ? The increasing use of CFCs is the cause of ozone depletion and the formation of ozone holes. Ozone can absorb ultraviolet rays with wavelengths of 200–300 nanometers, thereby reducing the harm that these rays cause to living organisms (including humans). If humanity does not take measures to protect the atmospheric ozone layer, by 2075 154 million people worldwide will suffer from skin cancer, 18 million people will develop cataracts, crop yields will decline by 7.5%, fishery yields will drop by 25%, and losses in materials will amount to $4.7 billion. ? There are 13 million refugees worldwide due to environmental problems, a number that is close to that of refugees caused by **conflicts and** **disasters**. According to a survey conducted in 1982, environmental pollution caused losses of nearly 50 billion yuan per year in our country, while ecological damage resulted in losses of over 30 billion yuan; together these amounts totaled more than 80 billion yuan. Conservatively estimated, by the year 2000, China’s economic losses due to air pollution would amount to 200 billion yuan per year, accounting for about 1.2% of that year’s national income. ?